To investigate cutaneous macromolecular biosynthesis; and to define the effect of vitamin A in inhibiting keratinization, in embryonic skin, normal adult skin, and in benign and malignant lesions. Chick embryo skin or skin from patients with Darier's Disease was incubated both with and without vitamin A in a water bath shaker at 37 degrees C for 2-6 hours in the presence of labelled precursors. Occasional experiments involved 3 day organ culture of chick skin with and without vitamin A prior to exposure to radioactivity. After incubation, specimens were prepared for biochemical extraction and analysis. Various macromolecular fractions (DNA, RNA, protein, and glycoprotein) were isolated using standard methodology. The specific activities of these fractions were determined, and separation and characterization of individual molecular species was defined using polyacrylamide gel electrophoresis. Quantitative and qualitative changes in response to experimental design could be readily followed by banding patterns assayed both spectrophotometrically and by liquid scintillation counting.